An Electronic Article Surveillance (EAS) system is designed to prevent unauthorized removal of an item from a controlled area. A typical EAS system may comprise a monitoring system and one or more security tags. The monitoring system may create a surveillance or interrogation zone at an access point for the controlled area. A security tag may be fastened to an item, such as an article of clothing. If the tagged item enters the interrogation zone, an alarm may be triggered indicating unauthorized removal of the tagged item from the controlled area.
Some EAS systems may be arranged to detect multiple types of security tags. This may be accomplished using one or more transmitters communicating different types of signals into the interrogation zone. Such systems typically need multiple receivers to receive the corresponding different signals. The use of multiple receivers, however, may increase the complexity and cost of the EAS system. Consequently, there may be need for improvements in conventional EAS systems to solve these and other problems.